Process of and apparatus for separating ore materials from each other



R. S. TOWNE AND F. B. FLINN.

PROCESS OF'AND APPARATUS FOR SEPARATING ORE MATERIALS FROM EACH OTHER.

APPLICATION FILED sEPT. 12, I914- RENEWED IAN.5.1920.

1,378,920. Patented May-24,1921.

a5 5 -36 fl 32 umrsu STATES PATENT OFFICE.

ROBERT SAFFORD TOWNE, OF NEW YORK,.N. Y., AND FREDERICK B. FLINN OFORANGE, NEW JERSEY, ASSIGNORS, BY MESNE ASSIGNMENTS, TO PNEU- MATICPROCESS FLOTATION COMPANY, OF NEW YORK, N. Y., A CORPORA TION OFDELAWARE.

PROCESS OF AND APPARATUS FOR SEPARATING ORE MATERIALS FROM EACH OTHER.

Specification of Letters Patent.

Patented May 24, 1921.

Application filed September 12, 1914, Serial No. 861,433. Renewed.-January 5, 1920. Serial No. 349,639.

To allwhom it may concern.

Be it known that we, ROBERT S. Towns and 'FREDERICK B. FLINN, citizensof the United States, residing at New York and Orange, in the countiesof New Y'ork and Essex and States of New York and New Jersey,respectively, have invented certain new and useful Improvements inProcesses of and Apparatus for Separating Ore Materials from E QhOther,of which .the following is a specification, reference being had thereinto the accompanying drawmg This invention relates to a process fortreating ores for the purpose of separating the metalliferous particlesfrom the nonmetalliferous particles thereof; also to improvements inapparatus for carrylng out the process. The process is of the generalclass in which air, or equivalent gaseous body, is used for causing themetalliferous particles to separate from a fluid pulp mass and rise tothe surface; and is more particularly a process in the subclass in whichuse is made of relatively large bubbles formed by the introduction ofair, or its equivalent, into thepulp mass under slight pressure from anexternal alr body.

In carrying out a method of this sort a pulp is formed by comminglingthe ore in its original condition with water in suitable proportions,and, generally, there is added, at one stage or another, a quantum of011 or equivalent material for purposes now well known. A column of pulpis formed and the air is forced into the bottom part of this column,generally through a porous septum or diaphragm adapted, under properconditions ofdepth of column, pressure of air and degree of permeabilityof the septum, to form the relative]... large bubbles referred to. Thepulp is! elivered as a continuous supply to the column. 1

We have found that the ores must be considered'in several classes inrespect to'the general features of the process which we have devised. Inthe case of some ores we have found it more advantageous to deliver theincoming pulp at horizontal planes which are high relatively totheplanes of the porous septum, and in such cases the column may be ofrelatively lesser hor1zon tal dimensions and prolonged vertlcally asparticles, or

, horizontal area w 'ile it is moving downward; and in such cases wecause it to enter the ma1n pulp column from points at the periphery,ores of the sort referred to being so largely suspended in the waterthat they can be carried in a sheet to the center or pointsapproximating it.

But experience has brought us in contact with ores of another classwhich, either because of the greater specific gravity of their ecause ofthe relatively larger sizes of the particles which are introduced in thepulp, have a tendency to quickly separate from the suspending fluid, andtherefore are not subjected for a sufiiciently long time to theseparating action of the air.

Ores of this class we treat in the manner herein set forth. We findthat, as concerns these, it is better to deliver the pulp at or near thevertical axis of arelatively widely extended pulp column, permitting thesolid content particles to commence their descent onlines approximatelyclose to the vertical axis, and causing them to move outward as theydescend, so that they shall be subjected to repeated actions of the airglobules as the latter ascend.

In the drawings one of the numerous forms of apparatus is shown whichcan be employed in the treatment of ores such as are referred to;

Of the drawings,

Figure 1 is a vertical sectional view showing one form of mechanismembodying the invention;

Fig. 2 is a plan view of the mechanism shown in Fig. 1;

Fig. 3 is a fragmentary plan view, partly in section along the line 3-3of Fig. 1;

Fig. 4 is a fragmentary sectional view taken along the line 44 of Fig.3;

Fig. 5 is a fragmentary sectional view taken along the line 5-5 of Fig.3; and

Fig. 6 is a fragmentary sectional view taken along the line 66 of Fig.2.

Referring to the drawings,-

1 represents the main tank or receptacle,

cylindrical in form. It may conveniently be constructed of sheet metal,though any other suitable material may be used when preferred. Thereceptacle 1 is provided with a conical bottom 2 having radiallyinclined sides. At the lower end of the conical bottom 2 there is adischarge pipe 3 in which there is a valve 4. Connected with the pipeabove the valve is a branch discharge pipe 5 which is preferably formedof flexible hose.

Mounted in the receptacle, preferably at about the level at which thevertical side walls join the inclined bottom walls, is an airdistributing device indicated as a whole by 6. It comprises an upperplate 7 which is inclined downward from the center toward the periphery.The plate is porous and may be formed of some suitable medium Such assilica sponge, carborundum, a plurality of perforated metal plates,sheets of canvas, etc. Below the plate 7 is another plate 8 formed ofsheet metal or other imperforate material. Preferably the plate 8 isalso conical in form, it being inclined upward from the center towardthe periphery. Preferably the plates 7 and 8 are provided with largecentral apertures in which is fitted a vertical tube 9 which will befurther referred tobelow. The space between the two plates 7 and 8 ispreferably divided into annular chambers 10, 11 and 12 by meansofvertical partition walls 13, 14 and 15. The outer partition wall 13 isspaced away from the main side walls of the recep tacle, leaving anannular space 13*. The entire device 6 can be supported in any desiredway. As shown, it is carried by brackets 16, 16 extending upward fromthe inclined bottom wall 2.

Valved air pipes 17, 18 and 19 communicate respectively with thechambers 10, 11 and 12 and serve to supply air under pressure thereto.By means of the valves in the pipes the pressure in the, severalchambers can be regulated and controlled as deslred.

At the upper end of the tube 9, preferably some little distance abovethe plate 7, there is provided a cap or plate 20 which closes the upperend of the tube. At the periphcry of the plate 20 there is an annularlip or flange 21.

22 is a spout for delivering ore pulp to the plate 20. As shown, thespout is connected at one side to the wall of the receptacle 1 andreceives its supply through a pipe 23. In order to provide for the readydeflection of the upward flowing bubbles in 1 the receptacle, the spout22 is provided with oppositely inclined walls 23, 23 below its bottom,these walls serving to engage the bubbles and guide them to the sides ofthe spout.

In order to insure the delivery of the pulp from the spout 22 to theplate 20, we provide the tube 24 which is mounted vertically above thetube 9 and is of substantially the same size. The spout 22 communicateswith this tube 24 through an opening 25.

Positioned around the outside of the upper part of the main receptacle 1is an. annular bubble receiver 26. This has an inclined bottom 27 and atits lowermost part it is provided with a discharge spout 28.

As the tank 1 may be of large diameter,

we find it advisable to provide means formechanically assisting thedischarge of bubbles from the central parts thereof. The mechanism forengaging these central bubbles comprises the rotating blades 29, 29which are fixed on the hollow hub 30 surrounding the tube 24. As shown,the hub 30 carries rollers 31, 31 which engage the hub 30 to give therevoluble hub an antifriction bearing on the tube 24. The hub 30 isconnected by means of the arms 32, 32, supported on the ball pivot 33with a vertical shaft 34, which is driven by the motor 35 through thegearing 36.

In using the apparatus embodying our invention, the ore, after beingfirst pulverized (when pulverization is necessary) is formed into asuitable liquid pulp of which oil, when necessary, may bea constituent.This pulp is introduced in a stream into the spout 22, through which itflows into the tube 24 aforesaid, is engaged by the upward moving airbubbles, and the metalliferous particles thereof are caught by thebubbles and carried upward. The ore, as it passes downward and outward,is repeatedly acted upon by the bubbles with the result that when theperiphery is reached all of the metalliferous particles have been caughtby the bubbles and removed. The gangue or residue passes downward andoutward through the annular passageway 13, and then along the inclinedbottom wall 2 to the discharge pipe 3.

The airpressures in the chambers 10, 11 and 12 may be varied relativelyto each other in order to regulate and control the flow of air into thereceptacle. In practice, it is advisable, in using a machine of thischaracter, to vary the action of the air as the pulp moves radially, onerate of air supply being most eflicient near the center where the pulpis rich and its flow is slow, and another rate of air supply being mostefiicient near the and its flow is more rapld.

The level of the liquid in the tank 1 may be regulated and controlledeither by means of the valve 4:, or by means of the pipe 5. If

the pipe 5 is used the level of the liquid in the tank may be regulatedby raising or lowering the outer discharge end of the pipe.

The bubbles carrying the metalliferous particles in their films continueto move upward above thgpp ggface of the pulp and the successivelyemerging bubbles are carried upward by those that follow, with theresult that there is formed a bubble column extending to the top of thereceptacle wall. At the top of the Wall the bubbles move radiallyoutward under the influence of gravity and are discharged into theannular receiver 26. In this receiver many of the bubbles break up, butthose which remain, and the liquid resulting from those which haveburst, flow by gravity down the inclined bottom of the annular receiverand out through the spout 28.

On account of the size of the tank many of the bubbles at or near thecenter would break down before reaching the periphery 1f the expectationwere to have all of them reach the periphery by gravity alone. Therotary blades 29, 29 serve to engage the central bubbles and to pushthem outward near enough to the periphery so that they can reach it bygravity without breaking down.

We do not herein claim broadly the means for causing differences in theair action at different radial portions of the porous plate; and we donot herein claim broadly the means for assisting the removal of thebubbles from the center of the receptacle. These features are presentedand claimed broadly in our co-pending application Serial No. 861,432,filed on even date herewith.

We are aware that it has been proposed to provide rotary blades at thetop of a flu d receptacle in ore-treating apparatus. But in the earlierinstances referred to these were positioned directly in the horizontalplanes of the surface of the fluid, the purpose being to skim from saidsurface all the materials that rose thereto. The scrapers had thelrlower parts arranged in the horizontalplanes of the hydrostatic overflowof the fluld. In the present ,mechanism the central bubbleguiding rotarydevices are so positioned as to have all of their movable parts operatein planes considerably above the fluid surface so that the lower part ofthe bubble mass is allowed to freely rise and yet can begraduallyinduced to move outward toward the upper edge of the receptaclewall over which the bubbles flow or roll. The discharge controllingdevices at 4 and 5 are adjusted to hold the top or hydrostatic level ofthe fluid at a plane considerably below that of the upper edge of thereceptacle wall. The r0- tary bubble-moving device does not extend overthe whole area of the receptacle but is so arranged as to leave a freeannular space of considerable width. This rotary device is introducedwhen we use a receptacle of long diameter. With such an apparatus'thebubbles at the center tend to break down before they can reach theperiphery. It is preferable to avoid entirely having them impinged on byoutside bodies. But a suitably arranged and properly adjuited device ofthis sort can, where the area is large, be used at the center to inducea tendency of the bubbles to move gently toward the edge so that theycan, under their own gravity, roll or flowover the rim.

What we claim is:

1. In an apparatus for separating the metalliferous from thenon-metalliferous ingredients of an ore mass, the combination of a pulpreceptacle having a conical bottom with a discharge opening therein, aporous plate mounted, in the lower part of the receptacle with itsperiphery spaced slightly from the walls of the receptacle, means forsupplylng air under pressure below the said porous plate and forcing ittherethrough to form relatively large substantially uniformlydistributed air bubbles, throughout the area of the receptacle and meansfor supplying ore pulp to the receptacle above the said porous plate,the said pulp being acted upon by the said bubbles to remove themetalliferous ingredients therefrom flowing downward and outward overthe eriphery of the plate and into the space elow it.

2. In an apparatus for separating the metalliferous from thenon-metalliferous ingredients of an ore mass, the combination of a pulpreceptacle, a porous plate in the lower part of the receptacle inclineddownward along lines extending from the center to the periphery thereof,means for supplying air under pressure below the said porous plate andforcing it therethrough to form relatively large substantially uniformlydis tributed air bubbles, means for supplying ore pulp to the receptaclenear the center thereof above the said porous plate, the said pulpflowing downward and outward in the directions of inclination of thelate and being acted upon by the said bubb es to remove themetalliferous ingredients therefrom, and means for collecting theresulting barren pulp at the periphery of the plate and discharging itfrom the receptacle.

3. In an apparatus for separating the metalliferous from thenon-metalliferous ingredients of an ore mass, the combination of a pulpreceptacle, a porous plate in the lower part of the receptacle inclineddownward along lines extending from the center to the periphery thereof.means for supplying air under pressure below the said porous plate andforcing it therethrough to form relatively lar e substantially uniformlydistributed air bubbles, means for supplying ore pul to the receptaclenear the center thereo above the said porous plate, the said pulpflowing downward and outward in the directions of inclination of theplate and being acted upon by the said bubbles to remove themetalliferous ingredients therefrom, walls forming a chamber be? low thesaid plate for collecting the resulting barren pulp flowing over theperiphery of the plate, and means for discharging the barren pulp fromthe said chamber.

4. In an apparatus for separatin the metalliferous from the non-metallierous ingredients of an ore mass, the combination of a pulp receptacle,a porous late in the lower part of the receptacle in ined downward alonglines extending from the center to the periphery thereof, means forsupplying air under pressure below the sai porous plate and forcing ittherethrough to form relatively lar e substantially uniformlydistributed air bubbles, means for supplying ore pulp to the receptaclenear the center thereof above the said. porous plate, the said pulpflowing downward and outward in the directions of inclination of theplate and being acted upon by the said bubbles to remove themetalliferous ingredients therefrom, a wall below the said plate in theform of an inverted cone for collecting the resulting barren pulpflowing over the periphery of the plate, and means at the apex of thecone for discharging the pulp therefrom.

5. In an apparatus for separating the metalliferous from thenon-metalliferous ingredients of an ore mass, the combination of a pulpreceptacle, a porous plate in the lower part of the rece tacle inclineddownward along lines exten ing radially from the center to theperiphery-thereof, means for supplyin air under pressure below the saidporous p ate and forcing it therethrough to form relatively large airbubbles, means for causing the action of the air at one annular portionof the plate to differ from the action at another annular portion, meansfor supplying ore pulp to the receptacle at points near the centerthereof and above the said porous bottom, the said pulp flowing downwardand outward in the directions of inclination of the plate and beingacted u on by the said bubbles to remove the meta iferous ingredientstherefrom, and means for collecting and discharging from the receptaclethe resulting barren pulp which reachesthe lower peripheral parts of theplate.

6. In an apparatus for separating the metalliferous from thenon-metalliferous ingredients of an ore mass, the combination of a pulpreceptacle, a orous plate in the lower part of the receptac e, meansforv supplying air under pressure below the-said'porous plate andforcing it therethrou h to form relatively large substantially uni ormlydistributed air bubbles, a closed tube extending upward from the porousplate in the center of the receptacle, means for supplying ore pulp tothe receptacle at polnts above the said porous bottom arranged along theperiphery of the said tube, and said pulpbeing acted upon by the saidbubbles to remove the metalliferous ingredients therefrom, and means forcollecting and discharging from the receptacle the resulting barrenpulp.

7. In an apparatus for separating the met alliferous from thenon-metalliferous ingredients of an ore mass, the combination of a pulpreceptacle, a porous plate in the lower part of the receptacle, meansfor supplying air under pressure below the said porous plate and forcingit therethrough to form relatively large substantially uniformlydistributed air bubbles, a closed tube extending upward from the porousplatein theooi'lter of the. receptacle and terminating below the topthereof, a second tube above and in axial alinement with the first tubeand separated therefrom, means for supplying ore pulp to the second tubeto cause it to flow radially outward through the opening between thetubes, the said pulp being acted upon by the said bubbles to remove themetallifemul ingredients therefrom, and means for collecting anddischargin the receptacle the resulting barren pu p.

8. In an apparatus for separating the metalliferous from thenon-metalliferous ingredlnts of an ore mass, the combination of a pulpreceptacle, a porous plate in the lower part of the receptacle, meansfor supplying air under plate and orcihg it therethrough to formrelatively large substantially uniformly distributed air bubbles, aclosed tube extending upward from the porous plate in the center of thereceptacle and terminating below the to thereof, a second tube above andin axial almement with the first tube and separated therefrom, a spoutextending substantially horizontally from the periphery of thereceptacle to an aperture in the second tube for supplying ore pulp tothe said second tube, the said pulp flowing radially outward through theopening between the tubes and being acted upon by the said bubbles toremove the metalliferous ingredients there-v from, and means forcollectingand discharging from the receptacle the resulting barren P P-5?. In an apparatus for separatin the metalhferous from the non-metallierous in gredlents of an ore mass, the combination of a pulp receptacle,a porous plate in the lower part of the receptacle, means for supplyingan under premure below the said porous from 1pressure below the saidporous pate and forcing it therethrough to form relatively largesubstantially uniformly distributed air bubbles, a spout extendingsubstantially horizontally from the periphery of the receptacle to apoint near the center for suplying ore pulp to the central part of thereceptacle, the said pulp flowing radially outward and being acted uponby the said bubbles to remove the metalliferous ingredients therefrom,sharply inclined walls at the bottom of the spout for deflecting u wardmoving bubbles to the sides thereo and means for collecting anddischarging from the receptacle the resulting barren pulp.

10. In a mechanism for separatin the metalliferous from the non-metallierous constituents of an ore mass, the combinatlon of a pulp receptacle,a porous plate in the lower part of the receptacle, means for supplyingair under pressure below the said porous plate and forcing ittherethrough to form relatively large substantially uniformlydistributed air bubbles, means for supplying ore pulp to the receptacleabove the said porous plate, the said pulp being acted upon by the saidbubbles to remove the metalliferous constituents therefrom, means forcollecting and discharging the resulting barren pulp from thereceptacle, means without and around the peripheryof the receptacle forreceiving bubbles dlscharged over the walls thereof, and a movabledevice at the center of the upper part of the receptacle for engaglng bubles and moving them outward toward the said receiving means, saidreceptacle having a horizontal diameter which is long relatively to thecapacity of the bubbles to pass from the center to the edge, and thesaid bubblemoving device being arranged to operate in planes above thesurface of the pulp and toleave a wide exposed area adjacent theperipher of the receptacle.

11. n a mechanism for separatin the metalliferous from; the non-metallierous constituents of an ore mass, the combination of a pulp rece tacle,a porous plate 1n the lower part of t e receptacle, means for supplyingair under pressure below the said porous p ate and forcing ittherethrough to form relatively large substantially 11111- formlydistributed air bubbles, means for supplying ore pulp t0 the reeeptacleabove the said porous ate, the said pulp being acted upon by t e saidbubbles to remove the metalliferous constituents therefrom, means forcollecting and discharging the resulting barren pulp from thereceptacle, means without and around the eriphery of the receptacle forreceivln bu bles discharged over the walls thereo and a rotatable deviceat the center of the upper art of the receptacle havmg outward exten mgblades for engaging bubbles and moving them outward toward the saidreceivin means, said receptacle having a horizonta diameter which islong relatively to the capacity of the bubbles to pass from the centerto the edge, and the said bubblemoving device being arranged to operatein planes above the surface of the pulp and to leave a wide exposed areaadjacent the periphery of the receptacle.

12. The herein described process for separating the metalliferous fromthe non-metalliferous particles of an ore mass, which consists informing a body of li uid pulp of the ore having a relatively wi ehorizontal cross area forming bubbles of air at the bottom of the bodyand permitting them to rise therethrough and adhere to and remove themetalliferous particles, introducing fresh pul into the said pulp bodyat points considera ly above the plane of bubble formation and near, thevertical central axis of the receptacle, causing the said pulp to movedownward at the center of the body to the bottom and then outward acrossthe vertical paths of the bubbles, permitting the barren pulp to movevertically past the planes of bubble formation, collectin andtemporarily retaining it in a region ielow said planes, and dischargingit from said region under optional control.

13. The herein described process for separating the metalliferous fromthe non-metalliferous particles of an ore mass, which consists informing a body of liquid pul of the ore having a relatively widehorizontal cross area, forming bubbles of air at the bottom of the saidbody of pulp at points remote from the peripheral portion of the pulpand permitting them to rise therethrough and adhere to and remove themetalliferous particles, introducing fresh pulp into the said pulp bodyat points considerably above the Plane of bubble formation and near thecenter of the mass of said bubbles, causin thesaid pulp to move bothdownward and outward in all directions relative to the center of themass of said bubbles and across the vertical lines of movement of thebubbles, permitting the barren pulp to move vertically past the planesof bubble formation, collecting and temporarily retaining the pulp in aregion below said planes, and discharging it from said region underoptional control.

In testimony whereof we afiix our signatures, in presence of twowitnesses.

ROBERT SAFFORD TOWNE. FREDERICK B. FLINN.

Witnesses:

DAVID Soo'r'r, R. E. SAFFoRD.

